List of References Cited in This Section (United States Patents)
2,040,248May 12, 1936Dvorak3,847,263Nov. 12, 1974X5,166,669Nov. 27, 1992Romberg5,836,705Nov. 17, 1998Choate5,879,089Mar. 9, 1999Armel6,053,647Apr. 25, 2000Parkinson
The preferred embodiments of the keyboard patents listed here are shown in FIGS. 2 through 7 of the Drawings, for ease of reference. An additional list of world-wide keyboard patents is also included below. The members of that list have some common attributes, which allow them to be addressed as a group.
Standard Qwerty Keyboard
The current Standard keyboard is also known as the Qwerty keyboard, based on the first six letters on the left hand side of the upper row of alphabetic characters. It was designed for mechanical typewriters around 1872 by C. Latham Sholes. Letters were arranged to prevent the jamming of mechanical keys, a design which also slows down typing. The Qwerty keyboard is poorly optimized for speed on an electronic keyboard, where mechanical key interference is no longer an issue. Regardless, the Qwerty keyboard is familiar to most keyboard users and is well entrenched in industry. Many improved keyboards have been proposed as alternates to the Standard, but these alternatives have not been broadly commercially accepted over the past one hundred and thirty years.
Dvorak Keyboard
In U.S. Pat. No. 2,040,248, of May 12, 1936, August Dvorak and William Dealey revealed an improved keyboard, with respect to the speed of typing and the reduction of finger reach and strain. They recorded the frequency of two letter sequences in the English language, called digraphs. Using this data, awkward key patterns were avoided, such as striking different keys with the same finger. The most frequently used letters were placed on the middle or “home” row, to minimize finger reach and potential strain. Due to the speed improvements and reduced strain which it offers typists, the Dvorak keyboard is widely acknowledged in industry as a keyboard design that is superior to the Qwerty keyboard.
One drawback of the Dvorak keyboard is the random placement of alphabetic characters, virtually all of which are in different locations from the Standard Qwerty keyboard. This makes transition from the Qwerty keyboard quite difficult. Another problem exists, in that two frequent letters, A and S, appear at small finger locations on the home row. Dvorak mentions that use of small fingers in typing is awkward, but places A and S at such locations regardless, so that all high frequency letters except R appear on the home row.
“X” Keyboard
In a Nov. 12, 1974 patent, U.S. Pat. No. 3,847,263, an alternate to the Dvorak keyboard was introduced by “X”, with many of the same attributes. For example, “X” positions most frequently used keys on the middle or home row of the keyboard. Letter frequencies in foreign languages other than English are also considered. The “X” keyboard has both dextral and sinistral versions, aimed at use by persons with dominant right and left hands, respectively. All vowels appear on the left hand side of the “X” keyboard, in its dextral version. Most vowels and consonants are interleaved in language, so this places many sequential key combinations on opposite hands. High frequency keys appear at both small finger locations in the “X” Keyboard. With many high frequency keys on the middle row, the “X” keyboard offers greater speed potential to a typist, relative to the Qwerty keyboard.
The two main drawbacks of the “X” keyboard are similar to those of the Dvorak keyboard. The “X” keyboard has a random arrangement of alphabetic letters, almost all of which differ from the Standard Qwerty locations. A new random arrangement of letters is seen as a significant barrier to the wide-spread use of any keyboard. As well, the “X” keyboard places two frequently used letters at small finger locations, namely O and S. This is seen as problematic, because small fingers are often less agile than other fingers.
Romberg/ASER Keyboard
U.S. Pat. No. 5,166,669 was granted Nov. 27, 1992, to Harvey D. Romberg. It outlines a keyboard layout aimed at reducing the difficulty in transition from the Standard Qwerty keyboard. A maximum of fifteen keys are moved from their Qwerty locations. Several high frequency letters move from their Qwerty locations to the home row, as occurs in Dvorak and “X” keyboards. The left hand side of the home row begins with the letter sequence A, S, E, R, leading to the name ASER Keyboard. The arrangement reduces finger reach from the home row to upper and lower rows. Reach reduction is aimed at both improving speed and reducing repetitive strain injuries.
Limitations are seen in the ASER keyboard. Six high frequency letters are moved to the home row, namely the letters: E, R, N, T, I and O. Because these letters are so common, it is remains difficult for a touch typist or a hunt style typist to adjust to the change. The goal of easing transition from the Qwerty layout is only partially achieved. Next, the ASER keyboard patent description does not explore digraphs or key sequences. Analysis shows that it is not well optimized in terms of placing digraphs on opposite hands. As well, the small finger is used for two high frequency letters on the home row, namely A and O. The last two factors indicate some limitation with respect to typing speed.
Choate/Red Hot Keyboard
Preceded by similar patents in 1994 and 1996, U.S. Pat. No. 5,836,705 was granted to John I. M. Choate on Nov. 17, 1998. Choate introduced a keyboard identified by the high frequency letters “As in Red Hot” on the middle or home row. Similar to the Romberg approach, there was a direct effort in the keyboard design to ease transition from the Standard Qwerty layout. No more than 16 letters move from their locations on the Qwerty layout, in “Red Hot” realizations of a keyboard. Six high frequency letters (E, I, O, T, N and R) are moved from Qwerty locations to new home row locations. The emphasis on home row letter location by Choate is aimed at reducing finger reach. Choate presents statistics showing that the Red Hot keyboard design significantly reduces “finger distance” traveled. This attribute is aimed at a reduction in repetitive stress injuries and carpal tunnel syndrome.
Choate also examines briefly the digraph statistics developed by Dvorak and Dealey. Choate notes that many of the frequent digraph pairs are now located on the home row, again reflecting a design aimed at reducing “finger distance” traveled. Placement of digraphs on opposite hands is not discussed by Choate and the layout is not optimized in that regard.
The main limitations seen in the Red Hot keyboard layout are similar to those of the ASER layout, discussed above. That is, six high frequency keys move from their Qwerty locations, so that transition from the standard may not be as easy as intended. As well, two high frequency letters (A and R) appear at small finger locations, which are awkward locations for many typists. Last, neither ASER nor Red Hot keyboards are optimized with respect to placement of high frequency digraphs on opposite hands. For the latter two reasons, there are typing speed limitations on both the ASER and Red Hot keyboards, as well as some ongoing difficulty in transition from Qwerty.
Armel/Central Keyboard
Another novel keyboard design was introduced by Gerald J. Armel, in U.S. Pat. No. 5,879,089, dated Mar. 9, 1999. Armel places an emphasis on the central region of the keyboard, which may be reached by the strongest and most dexterous fingers, the middle finger and forefinger, also called the “inner fingers”. As used here, the term “finger dexterity” includes both the physical and mental aspects of finger control and movement.
A preferred embodiment of the Armel/Central Keyboard shows the most frequently used letters of the English language, in the center of the upper, middle and lower rows of the keyboard as follows:
upper rowS, T, Rmiddle rowN, E, Alower rowI, O, UThis Central keyboard arrangement designed by Armel was aimed at users who may have difficulty using fingers other than inner fingers, for a variety of reasons.
One issue that arises with the Armel keyboard, is the placement of letters in “random” locations, nearly all of which are different from Standard Qwerty locations. History shows that this is a major inhibitor to keyboard adoption in practice. In addition, the Central keyboard discussed here is not well optimized with respect to placement of digraphs of opposite hands. A central positioning of high frequency letters causes many key sequences to be performed by the same finger or by adjacent fingers. These factors suggest fundamental speed limitations in the Armel or Central keyboard layout.
Alphabetic Keyboards
There are a quite a number of keyboard patents which include key layouts in alphabetical order as one of their characteristics. So called “Alphabetic” keyboards have been defined as early as May 28, 1985, in U.S. Pat. No. 4,519,721, by Kathleen A. Gardener. A more recent Alphabetic keyboard is found in U.S. Pat. No. 6,053,647, dated Apr. 25, 2000, by John V. Parkinson. The Parkinson patent is chosen for reference because it discusses the optimization of two key sequences, or digraphs, and claims to be better than the Dvorak layout, in this respect. The Parkinson analysis is confined to digraphs on the same row. When the analysis is expanded to frequent key sequences on two rows, as outlined herein, both the current invention and the Dvorak keyboard are seen to be better optimized for digraphs on opposite hands than the Parkinson Alphabetic keyboard implementation of the year 2000.
Alphabetical order is aimed at ease of learning for new users or those who only use a keyboard infrequently. The logical arrangement of keys in alphabetical order makes letters easier to find and to remember, in comparison to a random layout. This is of benefit to entirely new users or possibly persons who must only use keyboards infrequently.
Alphabetic arrangements of keys represents a total departure from the Standard Qwerty arrangement of keys. Because there are many existing keyboard users, who are familiar with the Qwerty layout, there will be an on-going barrier to adoption of an Alphabetic key layout.
The interleaving of vowels and consonants in the order of the alphabet makes it difficult to optimize such layouts for speed. A predetermined letter ordering, whether along rows or columns, inhibits placement of digraphs on opposite hands, which is an important factor for speed. Parkinson has tried to optimize this factor and may be considered “best-in-class” among Alphabetic keyboards. Still, both the current invention and the Dvorak keyboard place more digraphs on opposite hands. As such, the current invention is expected to be faster for typing and easier for Qwerty transition than Alphabetic keyboards in general.
Other Keyboard Arrangements (US, International and PCT/WIPO Patents)
WO 01/73744 A1Oct. 4, 2001Woods, Debra L.WO 9906216Feb. 11, 1999Pittard, Arthur GeorgeU.S. Pat. No. 4,927,279May 22, 1990Morgan, Ruth B.FR 2611589Sep. 9, 1988Marsan, ClaudeU.S. Pat. No. 4,332,493Jun. 1, 1982Einbinder, HarveyEP 0066991Dec. 15, 1982Rushforth, Shelagh JaneGB 2041295Sep. 10, 1980Marsan, C.U.S. Pat. No. 3,929,216Dec. 30, 1975Einbinder, HarveyU.S. Pat. No. 3,698,533Oct. 17, 1972Illig et al.U.S. Pat. No. 3,698,532Oct. 17, 1972Dodds, IrvineU.S. Pat. No. 1,506,426Aug. 26, 1924Hoke, R. E.U.S. Pat. No. 1,512,001Oct. 14, 1924Cerny, J.
All of the above keyboard layouts share one important characteristic: the letter arrangements are entirely different from the Standard Qwerty keyboard and the majority of letters have moved from their Qwerty locations. Clearly, the patents listed here do not have ease of transition from the Standard Qwerty keyboard as one of their primary objectives or attributes. As such, they fall into a very different category from the current invention, which includes that constraint as one its primary goals.
The second and concurrent goal of the current invention is to increase the speed of typing. As outlined above, the Dvorak and “X” keyboards have been designed with that goal in mind. Both Dvorak and “X” keyboards have layouts which include the vowels A, E, I, O, and U on the left hand side of the middle row of the keyboard. This is a characteristic shared by a number of the patents listed here, namely: Pittard 1999, Marsan 1988 and 1980, Einbinder 1975, Dodds 1972, and Cerny 1924. As a group, they may be called “vowel oriented” keyboards. By separating vowels from high frequency consonants, frequent key sequences appear on opposite hands. Such a separation is one of the main elements contributing to higher speeds of typing on a keyboard.
It is not viewed as necessary to analyze in detail the behavior of all vowel oriented keyboards, to demonstrate that the current invention is novel and different from the group. Rather, it is felt to be sufficient to examine the keyboard which is generally acknowledged as “best-in-class” with respect to typing speed, namely the Dvorak keyboard from 1936. As evidence of that stature, the Dvorak keyboard is included as a “Language-Property” option in most versions of the Microsoft Windows Operating System (OS), and can be readily installed on computers with a Window OS. A second keyboard, the “X” arrangement of 1972 is analyzed in detail in this document. Examination of further individual vowel oriented keyboards is viewed as likely to be redundant; their behavior or properties are expected to fall within the range of behaviors exhibited by the Dvorak and “X” keyboards.
Multiple Letter Keyboard—Marsan, 1988
The 1988 patent by Marsan may be worth a brief mention, since it contains an example of a keyboard with multiple keys assigned to the frequent letters E and A in the French language. The multiple letters in the Marsan case are aimed at providing easy access to the use of accents grave (è) and aigu (é) on the letter E and accent grave on the letter A. This is not an uncommon approach to speeding typing on European language keyboards, which may apply a variety of accents to letters, often vowels. In the Marsan example, the variants of the letters E and A appear close to one another on the same side of the keyboard. In the current invention, two E keys are placed on opposite sides of the keyboard, with the objective of increasing the frequency of key sequences that may be struck by fingers of opposite hands. The usage of multiple keys in the current invention is different from that of the Marsan, 1988, keyboard or other keyboards with separate keys representing accents on vowels or other letters.
Concluding Remarks on the Background of the Invention
As noted above, vowel oriented keyboards are considered as a group, and the best performing keyboards in that category, the Dvorak and “X” keyboards, are examined in detail in this document, as background to the current invention.
Attributes of the Romberg and Choate keyboards are examined in detail herein, because those two arrangements are specifically aimed at easing transition from the Qwerty keyboard; no other keyboards have been identified with that stated objective. The Armel or Central keyboard has been examined, because of its emphasis on inner fingers, which is somewhat similar to the avoidance of small fingers. It is problematic in terms of transition from Qwerty, as well as speed potential.
An Alphabetic keyboard example was examined, since there are several known variants of keyboards with letter arrangements in alphabetical order, either along rows or up and down columns. All are similar, however, in that they constrain consonants in a manner that does not lend itself to optimization of key sequences on opposite hands. The alphabetical order chosen dictates consonant positions in each case. This imposes inherent speed limitations.
A patent by Marsan of 1988, with multiple occurrences of the frequent letters A and E, is seen to be quite different in design and intent than the current invention.
It is hoped, therefore, that the examination of existing patents and known keyboard designs, as covered in this document, may be a comprehensive review of the subject for the purpose of differentiating the current invention.